Geographical clock.



n. sc'numcusn.

Patented Nov. 4, I902.

2 Sheets-Shoot I Patented Nov. 4, I902.

H. SCHUMACHER.

GEOGRAPHICAL CLOCK.

-- (Applxc ntion filed A r. 2, 1901 2 Sheets Sheet 2.

ditferent meridians.

UNITED STATES PATENT. OFFI E.

HENRY SCIIUMACIIER, OF SAN FRANCISCO, CALIFORNIA.

GEOGRAPHICAL CLOCK.

SPECIFICATION forming part of Letters Patent No. 712,729, dated November 4, 1902.

" Application filed April 2, 1901. Serial Ne. 54,023- tNd ndelJ To all whom it may concern:

Be it known that I. HENRY SCHUMACHER, a citizen of the United States, residingin the city and county of San Francisco, State of California, haveinvented an Improvement in Timepieces; and I hereby declare the following to be a full, clear, and exact description of the same.

My invention relates to a device for in? stantly determining the time upon'any mew ridian in the .World and the relative time of It consists of the parts and the construction .and arrangement of parts hereinafter de tra'te the intermitten movement of the hour;

- and stationary outer part.

hand. Fig. 3 is a section of movable disk Fig. 4 isa section,

of same, showing relative position of driving .device and the hands. E

plied to an ordinary clock or timepiece.

.varied to suit requirements.

I have here illustrated my invention as ap- It will be manifest that the construction may be As here shown, the dial A is subdivided intohaltves, each of which .is divided to representthe twelve hours, wh ich are the ordinary subdivisions of time, and one of said subdivisions is designed to represent the hours from six in the morn.-

ing to sixat night, while the other may indi-- cate the hours from six at night to six'in the mornin that if ound more desirable the dial can be marked from one to twenty-four to cover the entire twenty-four hours. The central portion 2, interior to the dial, is here shown as forming what is known as a polar map, in hich the north pole forms the center and the n rthern hemisphere is mapped about this center. Meridians radiate from this polar center to the periphery, and this central portion of the map is independent of the dial, but is fixed to turn with the hour-hand 3 upon its central post or sleeve. 1

If it is desired to keep the time of any particular locality, as \Vashington, the clock is set with the hour-hand coinciding'with the meridian of Washingtomand as the clock runs the hour-hand and the central map or It will be understood, however,-

meridians will travel together, while the meridians of the map other than the one with which the hounhand coincides will point to different hours on the dial, and thus show at once the time at either of the'places through which the meridians pass.

In order to correctly indicate the times, I have arranged the figures on the dial to run from rightto left around the dial instead of from left to right, in the usual manner, as this correctly represents the movement of the earth with relatio'a to the sun while the clock is running. In order to operate this, the internal gearing of the clock would be arranged to cause the hour-hand and the meridian-map to turn totheleft instead of to the right. This being a simple mechanical contrivauce is not here illustrated.

If it is desired to cause the minute-hand to move to the right in order to correctly show the fractions of an hour, it can be done by iuterposing an idler-wheel, which will reverse the movement of the min u te-hand 1t and cause it to travel in the opposite direction from the movements of the hour-hand and meridianmap. The only object} in such a change wouldbe to enable the observer to note correctly thatthe time was five, ten, orfifteen minutes past' the hour without the mental calculation if the minute-hand was running in the opposite directin to that usually given it, since in that case fifteen minutes after the hour would at first glance appear to be fifteen minutes before the hour.

In order to show the time in the southern hemisphere without duplicating the apparatus, I have arranged a series of meridianlines upon projecting rays or spurs 5, which may extend from the central meridian-map outwardly, so as to coincide with the figures on the dial. Thusany meridians in the southern hemispheresuch as Melbourne, Calcutta, Cape Town, Rio J anei'ro, and Valparaisomay be indicated upon these projecting radial It-will be manifest that if the di'ahis subdivided to show twenty-four hours the rate of speed of the clock would have to be one- 'th'etwenty-fonr hours.

halft'hat which is usually given-that is to stead of making two circuits of the e 'honr-hand would only make one in The same arrangement would be made if the dial shows two sets of'figures" running from 1 to 12.

Thehour-hand of the clock may move slowly and continuously; butl prefer to move it over the hour-spaces byintermittent movement-s, so that the hour-hand will stand at one division of time until the hour is completed and will then move to the next division by a single movement.

As here illustrated, the stem or post upon which the minute-hand 3 is mount-ed turns tothe right and has a cam 5 fixed to turn with it. An arm 6, having a lug 7, is fulcrumed so that the lug rests upon the cam and may have any intervening antifrictional contact. As the minute-hand passes around the dial, the cam moves with it and the highest part, of the cam lifts the lever,vand when the cam has passed thelug'7a spring 8 acts to pull the lever down with a sudden movement,

which is allowed bythe abrupt olfset of thecam. The arm carries a pawl 9, which engages teeth of a racket-wheel 10, and this wheel is monnted'and turnable with'the'hour-hand 3,

v The space between the ratchet-teeth and the .lift of the arm and pawl equals the distance which the hour-hand is to mwe over the dial at each impulse. Therefore when the cam raises the pawl gradually during the movement of the minute-hand around the dial it will engage the following tooth of the ratchetwheel, and when the cam releases the lever the spring 8 will move the arm, pawl, and ratchet and instantly advance the'hour-hand one interval of the dial. 11 is a holding-pawl to prevent back movement of the ratchet.

Having thus described my invention, what I'claim as new, and desire to seen re by Letters Patent, is-.

1. The combinationin a timepiece of a fixed 'In witness whereof dial with time subdivisions thereon, hands adapted to travel over said dial, a disk concentric with said dial and turnable in unison with one of said hands designated as the hourhand, peripheral projections upon said dial which are movable over the time subdivisions of the fixed dial, said projections having sub- 'stantially atriangular shape, a polar map of one hemisphere upon the disk, and a segment of a polar map of the otherhemisphere upon each of said projections.

3. The combination in atlmepiece of a fixed annular dial with time subdivisions marked thereon, a central disk independent thereof having a polar map and meridians of the northern hemisphere radiating fromthe center to the periphery, time-indicating hands turnable about the common center whereby the meridians other than thht which coincides with the hour-hand will indicate correct time at those points, points or rays of substantially triangular shape projecting radially upon the periphery of said' disk and coinciding with the meridians of placesin the southern hemisphere whereby the relative time of all places in both hemispheres is simnltaneonslyindi cated.

I have hereunto set my hand.

HENRY s'onunxonna.

Witnesses:

' 'GEo'. H. STRONG, S. H. NOURSE. 

